Don't unconditionally set in_sync on newly added device in raid5_reshape
[safe/jmp/linux-2.6] / drivers / char / tty_ioctl.c
index 851cfcd..8e67d5c 100644 (file)
@@ -21,7 +21,6 @@
 #include <linux/module.h>
 #include <linux/bitops.h>
 #include <linux/mutex.h>
-#include <linux/smp_lock.h>
 
 #include <asm/io.h>
 #include <asm/uaccess.h>
 
 
 /**
+ *     tty_chars_in_buffer     -       characters pending
+ *     @tty: terminal
+ *
+ *     Return the number of bytes of data in the device private
+ *     output queue. If no private method is supplied there is assumed
+ *     to be no queue on the device.
+ */
+
+int tty_chars_in_buffer(struct tty_struct *tty)
+{
+       if (tty->ops->chars_in_buffer)
+               return tty->ops->chars_in_buffer(tty);
+       else
+               return 0;
+}
+EXPORT_SYMBOL(tty_chars_in_buffer);
+
+/**
+ *     tty_write_room          -       write queue space
+ *     @tty: terminal
+ *
+ *     Return the number of bytes that can be queued to this device
+ *     at the present time. The result should be treated as a guarantee
+ *     and the driver cannot offer a value it later shrinks by more than
+ *     the number of bytes written. If no method is provided 2K is always
+ *     returned and data may be lost as there will be no flow control.
+ */
+int tty_write_room(struct tty_struct *tty)
+{
+       if (tty->ops->write_room)
+               return tty->ops->write_room(tty);
+       return 2048;
+}
+EXPORT_SYMBOL(tty_write_room);
+
+/**
+ *     tty_driver_flush_buffer -       discard internal buffer
+ *     @tty: terminal
+ *
+ *     Discard the internal output buffer for this device. If no method
+ *     is provided then either the buffer cannot be hardware flushed or
+ *     there is no buffer driver side.
+ */
+void tty_driver_flush_buffer(struct tty_struct *tty)
+{
+       if (tty->ops->flush_buffer)
+               tty->ops->flush_buffer(tty);
+}
+EXPORT_SYMBOL(tty_driver_flush_buffer);
+
+/**
+ *     tty_throttle            -       flow control
+ *     @tty: terminal
+ *
+ *     Indicate that a tty should stop transmitting data down the stack.
+ *     Takes the termios mutex to protect against parallel throttle/unthrottle
+ *     and also to ensure the driver can consistently reference its own
+ *     termios data at this point when implementing software flow control.
+ */
+
+void tty_throttle(struct tty_struct *tty)
+{
+       mutex_lock(&tty->termios_mutex);
+       /* check TTY_THROTTLED first so it indicates our state */
+       if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
+           tty->ops->throttle)
+               tty->ops->throttle(tty);
+       mutex_unlock(&tty->termios_mutex);
+}
+EXPORT_SYMBOL(tty_throttle);
+
+/**
+ *     tty_unthrottle          -       flow control
+ *     @tty: terminal
+ *
+ *     Indicate that a tty may continue transmitting data down the stack.
+ *     Takes the termios mutex to protect against parallel throttle/unthrottle
+ *     and also to ensure the driver can consistently reference its own
+ *     termios data at this point when implementing software flow control.
+ *
+ *     Drivers should however remember that the stack can issue a throttle,
+ *     then change flow control method, then unthrottle.
+ */
+
+void tty_unthrottle(struct tty_struct *tty)
+{
+       mutex_lock(&tty->termios_mutex);
+       if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
+           tty->ops->unthrottle)
+               tty->ops->unthrottle(tty);
+       mutex_unlock(&tty->termios_mutex);
+}
+EXPORT_SYMBOL(tty_unthrottle);
+
+/**
  *     tty_wait_until_sent     -       wait for I/O to finish
  *     @tty: tty we are waiting for
  *     @timeout: how long we will wait
@@ -58,20 +153,21 @@ void tty_wait_until_sent(struct tty_struct *tty, long timeout)
 
        printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf));
 #endif
-       if (!tty->driver->chars_in_buffer)
-               return;
        if (!timeout)
                timeout = MAX_SCHEDULE_TIMEOUT;
-       lock_kernel();
        if (wait_event_interruptible_timeout(tty->write_wait,
-                       !tty->driver->chars_in_buffer(tty), timeout) >= 0) {
-               if (tty->driver->wait_until_sent)
-                       tty->driver->wait_until_sent(tty, timeout);
+                       !tty_chars_in_buffer(tty), timeout) >= 0) {
+               if (tty->ops->wait_until_sent)
+                       tty->ops->wait_until_sent(tty, timeout);
        }
-       unlock_kernel();
 }
 EXPORT_SYMBOL(tty_wait_until_sent);
 
+
+/*
+ *             Termios Helper Methods
+ */
+
 static void unset_locked_termios(struct ktermios *termios,
                                 struct ktermios *old,
                                 struct ktermios *locked)
@@ -297,15 +393,23 @@ void tty_termios_encode_baud_rate(struct ktermios *termios,
                termios->c_cflag |= (BOTHER << IBSHIFT);
 #else
        if (ifound == -1 || ofound == -1) {
-               static int warned;
-               if (!warned++)
-                       printk(KERN_WARNING "tty: Unable to return correct "
+               printk_once(KERN_WARNING "tty: Unable to return correct "
                          "speed data as your architecture needs updating.\n");
        }
 #endif
 }
 EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate);
 
+/**
+ *     tty_encode_baud_rate            -       set baud rate of the tty
+ *     @ibaud: input baud rate
+ *     @obad: output baud rate
+ *
+ *     Update the current termios data for the tty with the new speed
+ *     settings. The caller must hold the termios_mutex for the tty in
+ *     question.
+ */
+
 void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud)
 {
        tty_termios_encode_baud_rate(tty->termios, ibaud, obaud);
@@ -390,13 +494,12 @@ EXPORT_SYMBOL(tty_termios_hw_change);
  *     is a bit of layering violation here with n_tty in terms of the
  *     internal knowledge of this function.
  *
- *     Locking: termios_sem
+ *     Locking: termios_mutex
  */
 
 static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
 {
-       int canon_change;
-       struct ktermios old_termios = *tty->termios;
+       struct ktermios old_termios;
        struct tty_ldisc *ld;
        unsigned long flags;
 
@@ -408,21 +511,9 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
        /* FIXME: we need to decide on some locking/ordering semantics
           for the set_termios notification eventually */
        mutex_lock(&tty->termios_mutex);
-
+       old_termios = *tty->termios;
        *tty->termios = *new_termios;
        unset_locked_termios(tty->termios, &old_termios, tty->termios_locked);
-       canon_change = (old_termios.c_lflag ^ tty->termios->c_lflag) & ICANON;
-       if (canon_change) {
-               memset(&tty->read_flags, 0, sizeof tty->read_flags);
-               tty->canon_head = tty->read_tail;
-               tty->canon_data = 0;
-               tty->erasing = 0;
-       }
-
-       /* This bit should be in the ldisc code */
-       if (canon_change && !L_ICANON(tty) && tty->read_cnt)
-               /* Get characters left over from canonical mode. */
-               wake_up_interruptible(&tty->read_wait);
 
        /* See if packet mode change of state. */
        if (tty->link && tty->link->packet) {
@@ -444,15 +535,15 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
                }
        }
 
-       if (tty->driver->set_termios)
-               (*tty->driver->set_termios)(tty, &old_termios);
+       if (tty->ops->set_termios)
+               (*tty->ops->set_termios)(tty, &old_termios);
        else
                tty_termios_copy_hw(tty->termios, &old_termios);
 
        ld = tty_ldisc_ref(tty);
        if (ld != NULL) {
-               if (ld->set_termios)
-                       (ld->set_termios)(tty, &old_termios);
+               if (ld->ops->set_termios)
+                       (ld->ops->set_termios)(tty, &old_termios);
                tty_ldisc_deref(ld);
        }
        mutex_unlock(&tty->termios_mutex);
@@ -468,7 +559,7 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
  *     functions before using change_termios to do the actual changes.
  *
  *     Locking:
- *             Called functions take ldisc and termios_sem locks
+ *             Called functions take ldisc and termios_mutex locks
  */
 
 static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
@@ -480,7 +571,9 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
        if (retval)
                return retval;
 
+       mutex_lock(&tty->termios_mutex);
        memcpy(&tmp_termios, tty->termios, sizeof(struct ktermios));
+       mutex_unlock(&tty->termios_mutex);
 
        if (opt & TERMIOS_TERMIO) {
                if (user_termio_to_kernel_termios(&tmp_termios,
@@ -510,8 +603,8 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
        ld = tty_ldisc_ref(tty);
 
        if (ld != NULL) {
-               if ((opt & TERMIOS_FLUSH) && ld->flush_buffer)
-                       ld->flush_buffer(tty);
+               if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+                       ld->ops->flush_buffer(tty);
                tty_ldisc_deref(ld);
        }
 
@@ -530,32 +623,74 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
        return 0;
 }
 
+static void copy_termios(struct tty_struct *tty, struct ktermios *kterm)
+{
+       mutex_lock(&tty->termios_mutex);
+       memcpy(kterm, tty->termios, sizeof(struct ktermios));
+       mutex_unlock(&tty->termios_mutex);
+}
+
+static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm)
+{
+       mutex_lock(&tty->termios_mutex);
+       memcpy(kterm, tty->termios_locked, sizeof(struct ktermios));
+       mutex_unlock(&tty->termios_mutex);
+}
+
 static int get_termio(struct tty_struct *tty, struct termio __user *termio)
 {
-       if (kernel_termios_to_user_termio(termio, tty->termios))
+       struct ktermios kterm;
+       copy_termios(tty, &kterm);
+       if (kernel_termios_to_user_termio(termio, &kterm))
                return -EFAULT;
        return 0;
 }
 
-static unsigned long inq_canon(struct tty_struct *tty)
+
+#ifdef TCGETX
+
+/**
+ *     set_termiox     -       set termiox fields if possible
+ *     @tty: terminal
+ *     @arg: termiox structure from user
+ *     @opt: option flags for ioctl type
+ *
+ *     Implement the device calling points for the SYS5 termiox ioctl
+ *     interface in Linux
+ */
+
+static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
 {
-       int nr, head, tail;
+       struct termiox tnew;
+       struct tty_ldisc *ld;
 
-       if (!tty->canon_data || !tty->read_buf)
-               return 0;
-       head = tty->canon_head;
-       tail = tty->read_tail;
-       nr = (head - tail) & (N_TTY_BUF_SIZE-1);
-       /* Skip EOF-chars.. */
-       while (head != tail) {
-               if (test_bit(tail, tty->read_flags) &&
-                   tty->read_buf[tail] == __DISABLED_CHAR)
-                       nr--;
-               tail = (tail+1) & (N_TTY_BUF_SIZE-1);
+       if (tty->termiox == NULL)
+               return -EINVAL;
+       if (copy_from_user(&tnew, arg, sizeof(struct termiox)))
+               return -EFAULT;
+
+       ld = tty_ldisc_ref(tty);
+       if (ld != NULL) {
+               if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+                       ld->ops->flush_buffer(tty);
+               tty_ldisc_deref(ld);
        }
-       return nr;
+       if (opt & TERMIOS_WAIT) {
+               tty_wait_until_sent(tty, 0);
+               if (signal_pending(current))
+                       return -EINTR;
+       }
+
+       mutex_lock(&tty->termios_mutex);
+       if (tty->ops->set_termiox)
+               tty->ops->set_termiox(tty, &tnew);
+       mutex_unlock(&tty->termios_mutex);
+       return 0;
 }
 
+#endif
+
+
 #ifdef TIOCGETP
 /*
  * These are deprecated, but there is limited support..
@@ -629,7 +764,7 @@ static void set_sgflags(struct ktermios *termios, int flags)
  *     Updates a terminal from the legacy BSD style terminal information
  *     structure.
  *
- *     Locking: termios_sem
+ *     Locking: termios_mutex
  */
 
 static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
@@ -666,12 +801,14 @@ static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars)
 {
        struct tchars tmp;
 
+       mutex_lock(&tty->termios_mutex);
        tmp.t_intrc = tty->termios->c_cc[VINTR];
        tmp.t_quitc = tty->termios->c_cc[VQUIT];
        tmp.t_startc = tty->termios->c_cc[VSTART];
        tmp.t_stopc = tty->termios->c_cc[VSTOP];
        tmp.t_eofc = tty->termios->c_cc[VEOF];
        tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */
+       mutex_unlock(&tty->termios_mutex);
        return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 }
 
@@ -681,12 +818,14 @@ static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars)
 
        if (copy_from_user(&tmp, tchars, sizeof(tmp)))
                return -EFAULT;
+       mutex_lock(&tty->termios_mutex);
        tty->termios->c_cc[VINTR] = tmp.t_intrc;
        tty->termios->c_cc[VQUIT] = tmp.t_quitc;
        tty->termios->c_cc[VSTART] = tmp.t_startc;
        tty->termios->c_cc[VSTOP] = tmp.t_stopc;
        tty->termios->c_cc[VEOF] = tmp.t_eofc;
        tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */
+       mutex_unlock(&tty->termios_mutex);
        return 0;
 }
 #endif
@@ -696,6 +835,7 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
 {
        struct ltchars tmp;
 
+       mutex_lock(&tty->termios_mutex);
        tmp.t_suspc = tty->termios->c_cc[VSUSP];
        /* what is dsuspc anyway? */
        tmp.t_dsuspc = tty->termios->c_cc[VSUSP];
@@ -704,6 +844,7 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
        tmp.t_flushc = tty->termios->c_cc[VEOL2];
        tmp.t_werasc = tty->termios->c_cc[VWERASE];
        tmp.t_lnextc = tty->termios->c_cc[VLNEXT];
+       mutex_unlock(&tty->termios_mutex);
        return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 }
 
@@ -714,6 +855,7 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
        if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
                return -EFAULT;
 
+       mutex_lock(&tty->termios_mutex);
        tty->termios->c_cc[VSUSP] = tmp.t_suspc;
        /* what is dsuspc anyway? */
        tty->termios->c_cc[VEOL2] = tmp.t_dsuspc;
@@ -722,6 +864,7 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
        tty->termios->c_cc[VEOL2] = tmp.t_flushc;
        tty->termios->c_cc[VWERASE] = tmp.t_werasc;
        tty->termios->c_cc[VLNEXT] = tmp.t_lnextc;
+       mutex_unlock(&tty->termios_mutex);
        return 0;
 }
 #endif
@@ -738,8 +881,8 @@ static int send_prio_char(struct tty_struct *tty, char ch)
 {
        int     was_stopped = tty->stopped;
 
-       if (tty->driver->send_xchar) {
-               tty->driver->send_xchar(tty, ch);
+       if (tty->ops->send_xchar) {
+               tty->ops->send_xchar(tty, ch);
                return 0;
        }
 
@@ -748,7 +891,7 @@ static int send_prio_char(struct tty_struct *tty, char ch)
 
        if (was_stopped)
                start_tty(tty);
-       tty->driver->write(tty, &ch, 1);
+       tty->ops->write(tty, &ch, 1);
        if (was_stopped)
                stop_tty(tty);
        tty_write_unlock(tty);
@@ -756,6 +899,33 @@ static int send_prio_char(struct tty_struct *tty, char ch)
 }
 
 /**
+ *     tty_change_softcar      -       carrier change ioctl helper
+ *     @tty: tty to update
+ *     @arg: enable/disable CLOCAL
+ *
+ *     Perform a change to the CLOCAL state and call into the driver
+ *     layer to make it visible. All done with the termios mutex
+ */
+
+static int tty_change_softcar(struct tty_struct *tty, int arg)
+{
+       int ret = 0;
+       int bit = arg ? CLOCAL : 0;
+       struct ktermios old;
+
+       mutex_lock(&tty->termios_mutex);
+       old = *tty->termios;
+       tty->termios->c_cflag &= ~CLOCAL;
+       tty->termios->c_cflag |= bit;
+       if (tty->ops->set_termios)
+               tty->ops->set_termios(tty, &old);
+       if ((tty->termios->c_cflag & CLOCAL) != bit)
+               ret = -EINVAL;
+       mutex_unlock(&tty->termios_mutex);
+       return ret;
+}
+
+/**
  *     tty_mode_ioctl          -       mode related ioctls
  *     @tty: tty for the ioctl
  *     @file: file pointer for the tty
@@ -772,6 +942,8 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 {
        struct tty_struct *real_tty;
        void __user *p = (void __user *)arg;
+       int ret = 0;
+       struct ktermios kterm;
 
        if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
            tty->driver->subtype == PTY_TYPE_MASTER)
@@ -807,18 +979,21 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
                return set_termios(real_tty, p, TERMIOS_OLD);
 #ifndef TCGETS2
        case TCGETS:
-               if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios))
-                       return -EFAULT;
-               return 0;
+               copy_termios(real_tty, &kterm);
+               if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
+                       ret = -EFAULT;
+               return ret;
 #else
        case TCGETS:
-               if (kernel_termios_to_user_termios_1((struct termios __user *)arg, real_tty->termios))
-                       return -EFAULT;
-               return 0;
+               copy_termios(real_tty, &kterm);
+               if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
+                       ret = -EFAULT;
+               return ret;
        case TCGETS2:
-               if (kernel_termios_to_user_termios((struct termios2 __user *)arg, real_tty->termios))
-                       return -EFAULT;
-               return 0;
+               copy_termios(real_tty, &kterm);
+               if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm))
+                       ret = -EFAULT;
+               return ret;
        case TCSETSF2:
                return set_termios(real_tty, p,  TERMIOS_FLUSH | TERMIOS_WAIT);
        case TCSETSW2:
@@ -836,41 +1011,67 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
                return set_termios(real_tty, p, TERMIOS_TERMIO);
 #ifndef TCGETS2
        case TIOCGLCKTRMIOS:
-               if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked))
-                       return -EFAULT;
-               return 0;
+               copy_termios_locked(real_tty, &kterm);
+               if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
+                       ret = -EFAULT;
+               return ret;
        case TIOCSLCKTRMIOS:
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
-               if (user_termios_to_kernel_termios(real_tty->termios_locked,
+               copy_termios_locked(real_tty, &kterm);
+               if (user_termios_to_kernel_termios(&kterm,
                                               (struct termios __user *) arg))
                        return -EFAULT;
+               mutex_lock(&real_tty->termios_mutex);
+               memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios));
+               mutex_unlock(&real_tty->termios_mutex);
                return 0;
 #else
        case TIOCGLCKTRMIOS:
-               if (kernel_termios_to_user_termios_1((struct termios __user *)arg, real_tty->termios_locked))
-                       return -EFAULT;
-               return 0;
+               copy_termios_locked(real_tty, &kterm);
+               if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
+                       ret = -EFAULT;
+               return ret;
        case TIOCSLCKTRMIOS:
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
-               if (user_termios_to_kernel_termios_1(real_tty->termios_locked,
+               copy_termios_locked(real_tty, &kterm);
+               if (user_termios_to_kernel_termios_1(&kterm,
                                               (struct termios __user *) arg))
                        return -EFAULT;
-                       return 0;
+               mutex_lock(&real_tty->termios_mutex);
+               memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios));
+               mutex_unlock(&real_tty->termios_mutex);
+               return ret;
 #endif
+#ifdef TCGETX
+       case TCGETX: {
+               struct termiox ktermx;
+               if (real_tty->termiox == NULL)
+                       return -EINVAL;
+               mutex_lock(&real_tty->termios_mutex);
+               memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox));
+               mutex_unlock(&real_tty->termios_mutex);
+               if (copy_to_user(p, &ktermx, sizeof(struct termiox)))
+                       ret = -EFAULT;
+               return ret;
+       }
+       case TCSETX:
+               return set_termiox(real_tty, p, 0);
+       case TCSETXW:
+               return set_termiox(real_tty, p, TERMIOS_WAIT);
+       case TCSETXF:
+               return set_termiox(real_tty, p, TERMIOS_FLUSH);
+#endif         
        case TIOCGSOFTCAR:
-               return put_user(C_CLOCAL(tty) ? 1 : 0,
+               copy_termios(real_tty, &kterm);
+               ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0,
                                                (int __user *)arg);
+               return ret;
        case TIOCSSOFTCAR:
                if (get_user(arg, (unsigned int __user *) arg))
                        return -EFAULT;
-               mutex_lock(&tty->termios_mutex);
-               tty->termios->c_cflag =
-                       ((tty->termios->c_cflag & ~CLOCAL) |
-                        (arg ? CLOCAL : 0));
-               mutex_unlock(&tty->termios_mutex);
-               return 0;
+               return tty_change_softcar(real_tty, arg);
        default:
                return -ENOIOCTLCMD;
        }
@@ -884,19 +1085,18 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
        if (retval)
                return retval;
 
-       ld = tty_ldisc_ref(tty);
+       ld = tty_ldisc_ref_wait(tty);
        switch (arg) {
        case TCIFLUSH:
-               if (ld && ld->flush_buffer)
-                       ld->flush_buffer(tty);
+               if (ld && ld->ops->flush_buffer)
+                       ld->ops->flush_buffer(tty);
                break;
        case TCIOFLUSH:
-               if (ld && ld->flush_buffer)
-                       ld->flush_buffer(tty);
+               if (ld && ld->ops->flush_buffer)
+                       ld->ops->flush_buffer(tty);
                /* fall through */
        case TCOFLUSH:
-               if (tty->driver->flush_buffer)
-                       tty->driver->flush_buffer(tty);
+               tty_driver_flush_buffer(tty);
                break;
        default:
                tty_ldisc_deref(ld);
@@ -907,19 +1107,12 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
 }
 EXPORT_SYMBOL_GPL(tty_perform_flush);
 
-int n_tty_ioctl(struct tty_struct *tty, struct file *file,
+int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
                       unsigned int cmd, unsigned long arg)
 {
-       struct tty_struct *real_tty;
        unsigned long flags;
        int retval;
 
-       if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
-           tty->driver->subtype == PTY_TYPE_MASTER)
-               real_tty = tty->link;
-       else
-               real_tty = tty;
-
        switch (cmd) {
        case TCXONC:
                retval = tty_check_change(tty);
@@ -952,15 +1145,6 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file,
                return 0;
        case TCFLSH:
                return tty_perform_flush(tty, arg);
-       case TIOCOUTQ:
-               return put_user(tty->driver->chars_in_buffer ?
-                               tty->driver->chars_in_buffer(tty) : 0,
-                               (int __user *) arg);
-       case TIOCINQ:
-               retval = tty->read_cnt;
-               if (L_ICANON(tty))
-                       retval = inq_canon(tty);
-               return put_user(retval, (unsigned int __user *) arg);
        case TIOCPKT:
        {
                int pktmode;
@@ -986,4 +1170,4 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file,
                return tty_mode_ioctl(tty, file, cmd, arg);
        }
 }
-EXPORT_SYMBOL(n_tty_ioctl);
+EXPORT_SYMBOL(n_tty_ioctl_helper);